Electrical Equipment wanted to purchase for 2 new ball mills and new concentrator plant construction
Our client is purchasing 2 x 18 foot in diameter by 30 feet long ball mills with an installed power of 5.5 MW for a new mineral project
Our client is in the process of designing and building a concentrator plant to process ROM material that has a bond work index of 14) which will be commissioned at the end of 2009.
They have a conventional MF1 circuit and plan to treat the Run of Mine material through crushers to produce a nominal minus 100mm material, which will then be fed into two primary ball mills with an installed power of 5.5MW each.
These mills will reduce the ore to minus 75 microns. The headfeed to the crushers will be 500 tons per hour and then to each primary mill, 250 tons per hour.
WANTED to BUY
Mill Motors - Medium Voltage 11kV 3 phase squirrel cage and wound rotor
- Motor shall be manufactured for continuous running duty type S1 with a rating class for continuous duty. The rated output of the motor shall be given in the data sheet.
- The number of poles and synchronous speed shall be given in the data sheet.
- The motor shall be capable of carrying 150% of rated current for 2 minutes when running at the rated voltage and frequency.
- The motor breakdown or maximum torque developed between standstill and rated speed shall not be less than 1,6 times the rated torque with rated voltage and rated frequency applied.
- The motor shall be capable of withstanding an excess torque of 1,6 times the rated torque for a period of 15 seconds without stalling or an abrupt change in speed.
- Full load slip shall not exceed 2% of the rated synchronous speed.
- The motor is to be suitable for use on either a solidly earthed or resistive earthed system. A resistive earthed system will be limited to 350 Amp for 30 seconds through a neutral earthing compensator resistor.
- The motor insulation systems shall have a thermal classification of Class F in accordance with the requirements of SABS IEC 60085 and be suitable for operating at any altitude up to 1650 metres above sea level with an ambient air temperature of 40C. The temperature rise shall not exceed Class B minus 10C (stator temperature 70K rise by resistance) when tested at nominal voltage, frequency and rating in accordance with SABS IEC 60034-2 and SABS IEC 60034-2A at an ambient temperature of 40C and corrected for 1650 masl.
- Single bus-bar 11000v 25kA 95kV BIL metalclad withdrawable modular switchgear.
- Bus-bar rating 2000A
- Incomers 2000A
- Bus-section panel with joggle chamber to be equipped with Fire-wall bus-trunking 1400mm long either side of panel. 2000A. 25kA 95kA BIL
- Feeder panels 800A 25kA 95kA BIL
- PFC feeder panel 25kA 95kA BIL
- All protection relays to be of the electronic pattern. Incomers to be fitted with Enermax or equal power management relay.
- Oil cooled distribution transformers 11000/550v Dyn11, free breathing, built to IEC 76/SABS 780, complete with MV & LV cable boxes, skid under-base, oil conservator and silica gel breather
- Fitted with Buchholz relay, dial thermometer and marshalling box
- LV neutrals to be external and transformer supplied with an NER of 63.5 ohms
- Sizes required are: 2000kVA (7 off), 1600kVA (3 off) and 630kVA (1 off)
- MV compartment
- SF6 Ring Main Unit (Merlin & Gerin preferred) complete with VIP35 protection relay or equal, Elastimold connectors (if required) and neon indication on both ring switches cable side.
Three phase 11000/550/400v Dyn11yn11, ONAN, sealed transformer built to IEC 76/SABS 780
- Complete with main MCCB and Tertiary MCCB, MDI ammeters and CTs, one voltmeter and fuses, busbars, wiring, labels & statutory signs
Sizes and quantity required
1 x 315kVA(11000/550v) + 50kVA(400v)
1 x 200kVA(11000/550v)+ 50kVA(400v)
Also as above but transformer as follows:-
1 x 630kVA 11000/400v
2 x 315kVA 11000/400v
1 x 315kVA 11000/550v
Phone: +61 422811261
Fax: +61 3 9816 9048
email: [email protected]